a64c48f4f9
This fixes two problems: 1) #include SK_SOME_DEFINE doesn't work well for all our clients. 2) Things in include/ are #including things in src/, which we don't like. TBR=reed@google.com BUG=skia: Review URL: https://codereview.chromium.org/862983002
37 lines
1.0 KiB
C++
37 lines
1.0 KiB
C++
/*
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* Copyright 2014 Google Inc.
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*
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* Use of this source code is governed by a BSD-style license that can be
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* found in the LICENSE file.
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*/
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#ifndef SkBarriers_arm_DEFINED
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#define SkBarriers_arm_DEFINED
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static inline void sk_compiler_barrier() { asm volatile("" : : : "memory"); }
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template <typename T>
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T sk_acquire_load(T* ptr) {
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T val = *ptr;
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__sync_synchronize(); // Issue a full barrier, which is an overkill acquire barrier.
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return val;
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}
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template <typename T>
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T sk_consume_load(T* ptr) {
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T val = *ptr;
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// Unlike acquire, consume loads (data-dependent loads) are guaranteed not to reorder on ARM.
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// No memory barrier is needed, so we just use a compiler barrier.
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// C.f. http://preshing.com/20140709/the-purpose-of-memory_order_consume-in-cpp11/
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sk_compiler_barrier();
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return val;
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}
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template <typename T>
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void sk_release_store(T* ptr, T val) {
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__sync_synchronize(); // Issue a full barrier, which is an overkill release barrier.
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*ptr = val;
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}
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#endif//SkBarriers_x86_DEFINED
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